This present invention relates to a fire protection system, and particularlY to a method and apparatus for electronic fire detection and/or fire extinguishment for use with chimneys, range hoods, commercial buildings, domestic dwellings, or other premises.
Conventional fire protection systems for commercial buildings and warehouses, and domestic dwellings, typically employ water sprinkler systems, or the like, in which one or more spray nozzles are employed to direct water or other fire extinguishate onto a fire. These sprinkler systems are usually pressurized either with air or water, and are actuated in response to the melting of fusible seals at the spray nozzles by a fire. Once activated, the sprinklers continue to operate until the source of water or other extinguishate is exhausted, or otherwise manually shut off.
These types of systems are undesirable for a number of reasons. First, since the amount of Water or extinguishate dispensed by the systems is not automatically controlled, it is quite possible that much of the extinguishate will be wasted, and may cause unnecessary damage to the protected area. In systems having a limited supply of extinguishate, this also adds the expense of having to fully recharge the system before it can be used again. Further, once one or more fusible seals have been melted by the heat of a fire, the sprinkler system obviously cannot be used again until those fusible seals are replaced. Again, this adds additional cost and inconvenience to the use of such a system.
In situations where a sprinkler system is actuated in an unattended building, such as a warehouse, it is possible that a fire could actuate the sprinkler system, be extinguished thereby, and go unnoticed for some period of time. It is possible, for example that the source of extinguishate could be unknowingly exhausted Further, even if it is known that the sprinkler system has been activated, it may be quite difficult to determine Which of a plurality of fusible seals located throughout a large building have been melted.